The invention relates to a sighting device for releasably mounting on the blade of a golf putter.
One of the most difficult operations in playing the game of golf is putting the ball. The object of putting is to strike the ball so that it travels along a target path between the ball and hole to drop into the hole. In order to achieve a successful putt the bottom horizontal face or sole of the putter blade must be lined up in a horizontal plane and the front or putting face of the putter must be arranged in a plane at right angles to the target line between the ball and hole. In addition, the ball must be struck as close as possible to the so called sweet-spot on the putting face. Normally this sweet-spot is located approximately mid-way along the putting face of the blade.
The co-ordination of all these requirements is difficult and studies have shown that more than half of the successful putts made are as a result of inter-compensationary errors in the execution of these steps.
One of the difficulties is that the human eye, unaided, is not capable of accurately drawing an imaginary target path between the ball and hole and subsequently aligning the putter and his own eye at the required angles to this line to achieve a successful putt.
Several sighting devices have been developed for golf putters however as will be discussed below none of these devices has been found to be particularly successful.
Known sighting devices may be broadly divided into four groups. Firstly there are devices which are mounted on the shaft of a putter which are unsatisfactory because they are generally unwieldly, adversely effect the natural balance of a club, and tend to cause parallax.
The second group of sighting devices are specially constructed golf putters. This specification describes a specially constructed golf putter in which is permanently mounted an inclined ball and target aligning mirror and a horizontal eye aligning mirror for aligning the eye of a player. Such golf putters are unsatisfactory primarily because they cannot be used under the rules of golf. It may be useful for a player to train using such a putter however when playing the game he must re-adjust back to his own putter without any sighting device and with the attendent disadvantages of a change in size, shape, weight and particularly balance. The most important disadvantage of this putter is that it is a separate item of equipment which the player must train with and is not a putter which can be used in play under the rules of golf.
The third class of sighting device is of the type which must be used in association with a particular putter. Generally the putter blade and sighting device have some form of complementary formations which are interengaged for mounting the device on the putter. Such devices essentially entail a combination of a specially constructed putter with a detachable sighting device. These devices not only suffer from the disadvantages of requiring a separate putter which cannot be used when playing under the rules of golf but are also optically unsatisfactory in that they only partially assist the player in putting the ball correctly in practice.
The final group of sighting devices are devices which it is claimed may be mounted on the blade of any putter and the blade is returned to its normal condition when the device is removed.
Optically, these devices are unsatisfactory in that while an inclined mirror on its own is of some assistance in lining a putt up correctly it is not fully accurate as the orientation of the putter face to the ball and the target path between the ball and pin will vary depending on the position of the player's eye. In addition, the device adversely effects the balance of the club with the result that if a ball is struck by the putter with the device attached with the same force as with the device removed not only will the ball be very unlikely to travel in the same direction but will not travel the same distance. In addition, the device described can only be mounted on putters having a shaft which extends from either end of the putter. Such putters are generally called bladed putters. It would be very difficult to use this device with a bladed putter having a curved back face and it would not be possible to mount such a device on a putter having a shaft which extends from the center of the putter blade--a so called center shafted putter.
In some of these devices, an inclined mirror is not sufficient to achieve the correct orientation of the putting face of a putter to a target line between the ball and pin as this will vary depending on the position of the player's eye. Further, the device can only be used with a putter blade having a flat continuous rear face. Only a relatively small percentage of putters presently on sale have such a flat continuous rear face. Further, such a device when attached to a putter adversely effects the normal balance of the putter and not only will a ball struck the same blow with the same putter with and without the sighting device attached be unlikely to travel in the same line but would also not travel the same distance.